1. Technical Field
The present invention relates to a pressing unit that is used for pressing a pressing member onto a pressing target, and a liquid ejecting apparatus provided with the pressing unit.
2. Related Art
A pressing mechanism used for pressing the pressing member onto the pressing target is used as a mechanism which transports a medium by pressing a transport driven roller onto a transport drive roller, as illustrated in JP-A-2006-56642 and JP-A-2013-230932.
In JP-A-2006-56642, a configuration is disclosed in which the pressing member is attached, in a detachable manner, to the pressing mechanism due to the engagement between a concave portion formed in a holder portion that holds a roller and a shaft portion that is provided on the pressing mechanism side, and due to the locking action between a plate spring shaped locking tool that is attached to the holder portion and the frame on the pressing mechanism side.
In JP-A-2013-230932, a configuration is disclosed in which paper retention force of a paper retaining roller is fixed by canceling out fluctuations in actuation force of coil springs caused by differences in paper thickness using two types of spring, the coil spring and an assistant coil spring.
However, JP-A-2006-56642 merely discloses a configuration in which the roller that serves as the pressing member is attached, in a detachable manner, to the pressing mechanism, and does not describe or suggest a configuration in which the pressing force of the roller is switched.
JP-A-2013-230932 merely discloses a configuration in which the pressing force is fixed using two types of spring, and there is no mention of using the pressing force of the roller to switch the pressing force.
Here, using a large format ink jet printer as an example, a plurality of transport driven rollers that serve as the pressing member are disposed in the width direction of the medium, and instead of the pressing force of all of the transport driven rollers being uniform, the pressing force is adjusted by the positions at which the transport driven rollers are attached.
However, in the configuration of the related art including JP-A-2006-56642 and JP-A-2013-230932, it is not possible to simply perform the switching of the pressing force.